Here's what Spicer says about it:

https://www.stovebolt.com/techtips/driveline/setup/index.html

Thanks, Grigg!

Unless the joint flexes a little, the lube doesn't circulate and the bearing runs dry from having the same point of contact all the time.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!